Superconducting series nanowire detector counting up to twelve photons

TL;DR

This paper presents a superconducting nanowire detector capable of resolving up to twelve photons simultaneously at telecommunication wavelengths, using a series array of NbN nanowires with integrated resistors.

Contribution

The authors developed and demonstrated a photon-number-resolving detector with a record resolution of twelve photons, advancing the scalability of superconducting photon detectors.

Findings

Thirteen distinct output levels for 0-12 photons detected.

Potential for scaling to larger photon numbers based on noise analysis.

Effective summing of voltage signals from nanowire array.

Abstract

We demonstrate a superconducting photon-number-resolving detector capable of resolving up to twelve photons at telecommunication wavelengths. It is based on a series array of twelve superconducting NbN nanowire elements, each connected in parallel with an integrated resistor. The photon-induced voltage signals from the twelve elements are summed up into a single readout pulse with a height proportional to the detected photon number. Thirteen distinct output levels corresponding to the detection of n=0-12 photons are observed experimentally. A detailed analysis of the excess noise shows the potential of scaling to an even larger dynamic range.